Chromate(2-), [4-[4-[(5-chloro-2-hydroxyphenyl)azo]-4,5-dihydro-3-methyl-5-oxo-1H-pyrazol-1-yl]benzenesulfonato(3-)][4-[(5-chloro-2-hydroxyphenyl)azo]-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-onato(2-)]-, sodium

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

Based on the prediction done using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the five closest read across substances, gene mutation was predicted for Chromate(2-), [4-[4-[(5-chloro-2-hydroxyphenyl)azo]-4,5-dihydro-3-methyl-5-oxo- 1H-pyrazol-1-yl] benzenesulfonato(3-)] [4-[(5-chloro-2-hydroxyphenyl)azo]- 2,4- dihydro-5-methyl-2-phenyl-3H-pyrazol-3-onato(2-)]-, sodium. The study assumed the use of Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 with S9 metabolic activation system. Chromate(2-), [4-[4-[(5-chloro-2- hydroxyphenyl)azo]-4,5-dihydro-3-methyl-5-oxo-1H-pyrazol-1-yl]benzenesulfonato(3-)] [4-[(5-chloro-2- hydroxyphenyl)azo]-2,4-dihydro-5-methyl-2-phenyl-3H- pyrazol-3-onato(2-)]-, sodium was predicted to not induce gene mutation in Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 in the presence of S9 metabolic activation system and hence, according to the prediction made, it is not likely to classify as a gene mutant in vitro.

 

Based on the predicted result it can be concluded that the substance is considered to be not toxic as per the criteria mentioned in CLP regulation.

Link to relevant study records

Reference

Endpoint:

in vitro gene mutation study in bacteria

Remarks:

Type of genotoxicity: gene mutation

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with limited documentation / justification

Justification for type of information:

Data is from OECD QSAR Toolbox version 3.4 and the supporting QMRF report has been attached

Qualifier:

according to guideline

Guideline:

other: Refer below principle

Principles of method if other than guideline:

Prediction is done using OECD QSAR Toolbox version 3.4, 2018

GLP compliance:

not specified

Type of assay:

bacterial reverse mutation assay

Specific details on test material used for the study:

- Name of test material (IUPAC name): Chromate(2-), [4-[4-[(5-chloro-2-hydroxyphenyl)azo]-4,5-dihydro-3-methyl-5-oxo-1H-pyrazol-1-yl]benzenesulfonato(3-)][4-[(5-chloro-2-hydroxyphenyl)azo]-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-onato(2-)]-, sodium
- Substance type: Organic

Target gene:

Histidine

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA 102

Details on mammalian cell type (if applicable):

Not applicable

Additional strain / cell type characteristics:

not specified

Cytokinesis block (if used):

No data

Metabolic activation:

with

Metabolic activation system:

S9 metabolic activation system

Test concentrations with justification for top dose:

No data

Vehicle / solvent:

No data

Untreated negative controls:

not specified

Negative solvent / vehicle controls:

not specified

True negative controls:

not specified

Positive controls:

not specified

Positive control substance:

not specified

Details on test system and experimental conditions:

No data

Rationale for test conditions:

No data

Evaluation criteria:

Prediction is done considering a dose dependent increase in the number of revertants/plate

Statistics:

No data

Species / strain:

S. typhimurium, other: TA 1535, TA 1537, TA 98 and TA 100

Metabolic activation:

not specified

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

not specified

Untreated negative controls validity:

not specified

Positive controls validity:

not specified

Additional information on results:

No data

Remarks on result:

no mutagenic potential (based on QSAR/QSPR prediction)

The prediction was based on dataset comprised from the following descriptors: "Gene mutation"
Estimation method: Takes highest mode value from the 7 nearest neighbours
Domain  logical expression:Result: In Domain

(((((((("a" or "b" or "c" or "d" )  and ("e" and ( not "f") )  )  and ("g" and ( not "h") )  )  and ("i" and ( not "j") )  )  and ("k" and ( not "l") )  )  and "m" )  and "n" )  and ("o" and "p" )  )

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as Anion by Substance Type

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as SN1 OR SN1 >> Nitrenium Ion formation OR SN1 >> Nitrenium Ion formation >> Aromatic azo OR SN1 >> Nitrenium Ion formation >> Unsaturated heterocyclic azo by DNA binding by OECD ONLY

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as AN2 OR AN2 >> Michael addition to activated double bonds in heterocyclic ring systems OR AN2 >> Michael addition to activated double bonds in heterocyclic ring systems >> Pyrazolone and Pyrazolidine Derivatives OR AN2 >> Schiff base formation with carbonyl compounds (AN2) OR AN2 >> Schiff base formation with carbonyl compounds (AN2) >> Pyrazolone and Pyrazolidine Derivatives OR Schiff base formation OR Schiff base formation >> Schiff base on pyrazolones and pyrazolidinones OR Schiff base formation >> Schiff base on pyrazolones and pyrazolidinones >> Pyrazolones and Pyrazolidinones by Protein binding by OASIS v1.4 ONLY

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as Acylation OR Acylation >> Direct Acylation Involving a Leaving group OR Acylation >> Direct Acylation Involving a Leaving group >> Acetates by Protein binding by OECD ONLY

Domain logical expression index: "e"

Referential boundary: The target chemical should be classified as No alert found by DNA binding by OASIS v.1.4

Domain logical expression index: "f"

Referential boundary: The target chemical should be classified as AN2 OR AN2 >>  Michael-type addition, quinoid structures OR AN2 >>  Michael-type addition, quinoid structures >> Flavonoids OR AN2 >>  Michael-type addition, quinoid structures >> Quinoneimines OR AN2 >>  Michael-type addition, quinoid structures >> Quinones and Trihydroxybenzenes OR AN2 >> Carbamoylation after isocyanate formation OR AN2 >> Carbamoylation after isocyanate formation >> N-Hydroxylamines OR AN2 >> Michael-type addition on alpha, beta-unsaturated carbonyl compounds OR AN2 >> Michael-type addition on alpha, beta-unsaturated carbonyl compounds >> Four- and Five-Membered Lactones OR AN2 >> Nucleophilic addition reaction with cycloisomerization OR AN2 >> Nucleophilic addition reaction with cycloisomerization >> Hydrazine Derivatives OR AN2 >> Schiff base formation OR AN2 >> Schiff base formation >> Dicarbonyl compounds OR AN2 >> Schiff base formation >> Halofuranones OR AN2 >> Schiff base formation >> Specific 5-Substituted Uracil Derivatives OR AN2 >> Schiff base formation by aldehyde formed after metabolic activation OR AN2 >> Schiff base formation by aldehyde formed after metabolic activation >> Geminal Polyhaloalkane Derivatives OR AN2 >> Shiff base formation after aldehyde release OR AN2 >> Shiff base formation after aldehyde release >> Specific Acetate Esters OR AN2 >> Shiff base formation for aldehydes OR AN2 >> Shiff base formation for aldehydes >> Haloalkane Derivatives with Labile Halogen OR Non-covalent interaction OR Non-covalent interaction >> DNA intercalation OR Non-covalent interaction >> DNA intercalation >> Acridone, Thioxanthone, Xanthone and Phenazine Derivatives OR Non-covalent interaction >> DNA intercalation >> Aminoacridine DNA Intercalators OR Non-covalent interaction >> DNA intercalation >> Coumarins OR Non-covalent interaction >> DNA intercalation >> DNA Intercalators with Carboxamide and Aminoalkylamine Side Chain OR Non-covalent interaction >> DNA intercalation >> Fused-Ring Nitroaromatics OR Non-covalent interaction >> DNA intercalation >> Fused-Ring Primary Aromatic Amines OR Non-covalent interaction >> DNA intercalation >> Organic Azides OR Non-covalent interaction >> DNA intercalation >> Polycyclic Aromatic Hydrocarbon and Naphthalenediimide Derivatives OR Non-covalent interaction >> DNA intercalation >> Quinolone Derivatives OR Non-covalent interaction >> DNA intercalation >> Quinones and Trihydroxybenzenes OR Non-covalent interaction >> DNA intercalation >> Specific 5-Substituted Uracil Derivatives OR Non-specific OR Non-specific >> Incorporation into DNA/RNA, due to structural analogy with  nucleoside bases    OR Non-specific >> Incorporation into DNA/RNA, due to structural analogy with  nucleoside bases    >> Specific Imine and Thione Derivatives OR Radical OR Radical >> Generation of ROS by glutathione depletion (indirect) OR Radical >> Generation of ROS by glutathione depletion (indirect) >> Haloalkanes Containing Heteroatom OR Radical >> Radical attack after one-electron reduction of diazonium cation OR Radical >> Radical attack after one-electron reduction of diazonium cation >> Arenediazonium Salts OR Radical >> Radical mechanism by ROS formation OR Radical >> Radical mechanism by ROS formation (indirect) or direct radical attack on DNA OR Radical >> Radical mechanism by ROS formation (indirect) or direct radical attack on DNA >> Organic Peroxy Compounds OR Radical >> Radical mechanism by ROS formation >> Five-Membered Aromatic Nitroheterocycles OR Radical >> Radical mechanism by ROS formation >> Organic Azides OR Radical >> Radical mechanism via ROS formation (indirect) OR Radical >> Radical mechanism via ROS formation (indirect) >> Acridone, Thioxanthone, Xanthone and Phenazine Derivatives OR Radical >> Radical mechanism via ROS formation (indirect) >> C-Nitroso Compounds OR Radical >> Radical mechanism via ROS formation (indirect) >> Conjugated Nitro Compounds OR Radical >> Radical mechanism via ROS formation (indirect) >> Coumarins OR Radical >> Radical mechanism via ROS formation (indirect) >> Flavonoids OR Radical >> Radical mechanism via ROS formation (indirect) >> Fused-Ring Nitroaromatics OR Radical >> Radical mechanism via ROS formation (indirect) >> Fused-Ring Primary Aromatic Amines OR Radical >> Radical mechanism via ROS formation (indirect) >> Geminal Polyhaloalkane Derivatives OR Radical >> Radical mechanism via ROS formation (indirect) >> Hydrazine Derivatives OR Radical >> Radical mechanism via ROS formation (indirect) >> N-Hydroxylamines OR Radical >> Radical mechanism via ROS formation (indirect) >> Nitro Azoarenes OR Radical >> Radical mechanism via ROS formation (indirect) >> Nitroaniline Derivatives OR Radical >> Radical mechanism via ROS formation (indirect) >> Nitroarenes with Other Active Groups OR Radical >> Radical mechanism via ROS formation (indirect) >> Nitrobiphenyls and Bridged Nitrobiphenyls OR Radical >> Radical mechanism via ROS formation (indirect) >> Nitrophenols, Nitrophenyl Ethers and Nitrobenzoic Acids OR Radical >> Radical mechanism via ROS formation (indirect) >> p-Aminobiphenyl Analogs OR Radical >> Radical mechanism via ROS formation (indirect) >> p-Substituted Mononitrobenzenes OR Radical >> Radical mechanism via ROS formation (indirect) >> Quinones and Trihydroxybenzenes OR Radical >> Radical mechanism via ROS formation (indirect) >> Single-Ring Substituted Primary Aromatic Amines OR Radical >> Radical mechanism via ROS formation (indirect) >> Specific Imine and Thione Derivatives OR Radical >> Radical mechanism via ROS formation (indirect) >> Thiols OR Radical >> ROS formation after GSH depletion (indirect) OR Radical >> ROS formation after GSH depletion (indirect) >> Quinoneimines OR SN1 OR SN1 >> Alkylation after metabolically formed carbenium ion species OR SN1 >> Alkylation after metabolically formed carbenium ion species >> Polycyclic Aromatic Hydrocarbon and Naphthalenediimide Derivatives OR SN1 >> Alkylation by carbenium ion formed OR SN1 >> Alkylation by carbenium ion formed >> Diazoalkanes OR SN1 >> Nucleophilic attack after carbenium ion formation OR SN1 >> Nucleophilic attack after carbenium ion formation >> N-Nitroso Compounds OR SN1 >> Nucleophilic attack after carbenium ion formation >> Pyrrolizidine Derivatives OR SN1 >> Nucleophilic attack after carbenium ion formation >> Specific Acetate Esters OR SN1 >> Nucleophilic attack after diazonium or carbenium ion formation OR SN1 >> Nucleophilic attack after diazonium or carbenium ion formation >> Nitroarenes with Other Active Groups OR SN1 >> Nucleophilic attack after metabolic nitrenium ion formation OR SN1 >> Nucleophilic attack after metabolic nitrenium ion formation >> Fused-Ring Primary Aromatic Amines OR SN1 >> Nucleophilic attack after nitrene formation OR SN1 >> Nucleophilic attack after nitrene formation >> Organic Azides OR SN1 >> Nucleophilic attack after nitrenium ion formation OR SN1 >> Nucleophilic attack after nitrenium ion formation >> N-Hydroxylamines OR SN1 >> Nucleophilic attack after nitrenium ion formation >> p-Aminobiphenyl Analogs OR SN1 >> Nucleophilic attack after nitrenium ion formation >> Single-Ring Substituted Primary Aromatic Amines OR SN1 >> Nucleophilic attack after nitrosonium cation formation OR SN1 >> Nucleophilic attack after nitrosonium cation formation >> N-Nitroso Compounds OR SN1 >> Nucleophilic attack after reduction and nitrenium ion formation OR SN1 >> Nucleophilic attack after reduction and nitrenium ion formation >> Conjugated Nitro Compounds OR SN1 >> Nucleophilic attack after reduction and nitrenium ion formation >> Fused-Ring Nitroaromatics OR SN1 >> Nucleophilic attack after reduction and nitrenium ion formation >> Nitro Azoarenes OR SN1 >> Nucleophilic attack after reduction and nitrenium ion formation >> Nitroaniline Derivatives OR SN1 >> Nucleophilic attack after reduction and nitrenium ion formation >> Nitroarenes with Other Active Groups OR SN1 >> Nucleophilic attack after reduction and nitrenium ion formation >> Nitrobiphenyls and Bridged Nitrobiphenyls OR SN1 >> Nucleophilic attack after reduction and nitrenium ion formation >> Nitrophenols, Nitrophenyl Ethers and Nitrobenzoic Acids OR SN1 >> Nucleophilic attack after reduction and nitrenium ion formation >> p-Substituted Mononitrobenzenes OR SN1 >> Nucleophilic substitution after glutathione-induced nitrenium ion formation OR SN1 >> Nucleophilic substitution after glutathione-induced nitrenium ion formation >> C-Nitroso Compounds OR SN1 >> Nucleophilic substitution on diazonium ion OR SN1 >> Nucleophilic substitution on diazonium ion >> Specific Imine and Thione Derivatives OR SN2 OR SN2 >> Acylation OR SN2 >> Acylation >> N-Hydroxylamines OR SN2 >> Acylation >> Specific Acetate Esters OR SN2 >> Acylation involving a leaving group  OR SN2 >> Acylation involving a leaving group  >> Haloalkane Derivatives with Labile Halogen OR SN2 >> Acylation involving a leaving group after metabolic activation OR SN2 >> Acylation involving a leaving group after metabolic activation >> Geminal Polyhaloalkane Derivatives OR SN2 >> Alkylation OR SN2 >> Alkylation >> Alkylphosphates, Alkylthiophosphates and Alkylphosphonates OR SN2 >> Alkylation, direct acting epoxides and related OR SN2 >> Alkylation, direct acting epoxides and related >> Epoxides and Aziridines OR SN2 >> Alkylation, direct acting epoxides and related after cyclization OR SN2 >> Alkylation, direct acting epoxides and related after cyclization >> Nitrogen and Sulfur Mustards OR SN2 >> Alkylation, direct acting epoxides and related after P450-mediated metabolic activation OR SN2 >> Alkylation, direct acting epoxides and related after P450-mediated metabolic activation >> Polycyclic Aromatic Hydrocarbon and Naphthalenediimide Derivatives OR SN2 >> Alkylation, nucleophilic substitution at sp3-carbon atom OR SN2 >> Alkylation, nucleophilic substitution at sp3-carbon atom >> Haloalkane Derivatives with Labile Halogen OR SN2 >> Alkylation, nucleophilic substitution at sp3-carbon atom >> Haloalkanes Containing Heteroatom OR SN2 >> Alkylation, nucleophilic substitution at sp3-carbon atom >> Specific 5-Substituted Uracil Derivatives OR SN2 >> Alkylation, ring opening SN2 reaction OR SN2 >> Alkylation, ring opening SN2 reaction >> Four- and Five-Membered Lactones OR SN2 >> Direct acting epoxides formed after metabolic activation OR SN2 >> Direct acting epoxides formed after metabolic activation >> Coumarins OR SN2 >> Direct acting epoxides formed after metabolic activation >> Quinoline Derivatives OR SN2 >> Direct nucleophilic attack on diazonium cation OR SN2 >> Direct nucleophilic attack on diazonium cation >> Arenediazonium Salts OR SN2 >> Direct nucleophilic attack on diazonium cation >> Hydrazine Derivatives OR SN2 >> DNA alkylation OR SN2 >> DNA alkylation >> Vicinal Dihaloalkanes OR SN2 >> Internal SN2 reaction with aziridinium and/or cyclic sulfonium ion formation (enzymatic) OR SN2 >> Internal SN2 reaction with aziridinium and/or cyclic sulfonium ion formation (enzymatic) >> Vicinal Dihaloalkanes OR SN2 >> Nucleophilic substitution at sp3 Carbon atom OR SN2 >> Nucleophilic substitution at sp3 Carbon atom >> Haloalkanes Containing Heteroatom OR SN2 >> Nucleophilic substitution at sp3 Carbon atom >> Halofuranones OR SN2 >> Nucleophilic substitution at sp3 Carbon atom >> Specific Acetate Esters OR SN2 >> Nucleophilic substitution at sp3 carbon atom after thiol (glutathione) conjugation OR SN2 >> Nucleophilic substitution at sp3 carbon atom after thiol (glutathione) conjugation >> Geminal Polyhaloalkane Derivatives OR SN2 >> SN2 at an activated carbon atom OR SN2 >> SN2 at an activated carbon atom >> Quinoline Derivatives OR SN2 >> SN2 attack on activated carbon Csp3 or Csp2 OR SN2 >> SN2 attack on activated carbon Csp3 or Csp2 >> Nitroarenes with Other Active Groups OR SN2 >> SN2 reaction at nitrogen-atom bound to a good leaving group OR SN2 >> SN2 reaction at nitrogen-atom bound to a good leaving group >> N-Acetoxyamines by DNA binding by OASIS v.1.4

Domain logical expression index: "g"

Referential boundary: The target chemical should be classified as Non binder, MW>500 by Estrogen Receptor Binding

Domain logical expression index: "h"

Referential boundary: The target chemical should be classified as Moderate binder, OH grooup OR Non binder, impaired OH or NH2 group OR Non binder, non cyclic structure OR Non binder, without OH or NH2 group OR Strong binder, NH2 group OR Strong binder, OH group OR Very strong binder, OH group OR Weak binder, NH2 group OR Weak binder, OH group by Estrogen Receptor Binding

Domain logical expression index: "i"

Referential boundary: The target chemical should be classified as Alkali Earth AND Halogens AND Non-Metals AND Transition Metals by Groups of elements

Domain logical expression index: "j"

Referential boundary: The target chemical should be classified as Alkaline Earth OR Metals by Groups of elements

Domain logical expression index: "k"

Referential boundary: The target chemical should be classified as Group 1 - Alkali Earth Li,Na,K,Rb,Cs,Fr AND Group 14 - Carbon C AND Group 15 - Nitrogen N AND Group 16 - Oxygen O AND Group 16 - Sulfur S AND Group 17 - Halogens Cl AND Group 17 - Halogens F,Cl,Br,I,At AND Group 6 - Trans.Metals Cr,Mo,W by Chemical elements

Domain logical expression index: "l"

Referential boundary: The target chemical should be classified as Group 17 - Halogens Br OR Group 17 - Halogens F by Chemical elements

Domain logical expression index: "m"

Similarity boundary:Target: CC1C{-}(N=Nc2cc(Cl)ccc2O{-}.[Cr]{2+}.O{-}c2ccc(Cl)cc2N=NC{-}2C(C)=NN(c3cccc(S(=O)(=O)O{-}.[Na]{+})c3)C2=O)C(=O)N(c2ccccc2)N=1
Threshold=30%,
Dice(Atom centered fragments)
Atom type; Count H attached; Hybridization

Domain logical expression index: "n"

Similarity boundary:Target: CC1C{-}(N=Nc2cc(Cl)ccc2O{-}.[Cr]{2+}.O{-}c2ccc(Cl)cc2N=NC{-}2C(C)=NN(c3cccc(S(=O)(=O)O{-}.[Na]{+})c3)C2=O)C(=O)N(c2ccccc2)N=1
Threshold=10%,
Dice(Atom centered fragments)
Atom type; Count H attached; Hybridization

Domain logical expression index: "o"

Parametric boundary:The target chemical should have a value of Molecular weight which is >= 705 Da

Domain logical expression index: "p"

Parametric boundary:The target chemical should have a value of Molecular weight which is <= 843 Da

Conclusions:

Chromate(2-), [4-[4-[(5-chloro-2- hydroxyphenyl)azo]-4,5-dihydro-3-methyl-5-oxo-1H-pyrazol-1-yl]benzenesulfonato(3-)] [4-[(5-chloro-2-hydroxyphenyl)azo]-2,4-dihydro-5-methyl-2-phenyl-3H- pyrazol-3-onato(2-)]-, sodium was predicted to not induce gene mutation in Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 in the presence of S9 metabolic activation system and hence, according to the prediction made, it is not likely to classify as a gene mutant in vitro.

Executive summary:

Based on the prediction done using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the five closest read across substances, gene mutation was predicted for Chromate(2-), [4-[4-[(5-chloro-2-hydroxyphenyl)azo]-4,5-dihydro-3-methyl-5-oxo-1H-pyrazol-1-yl] benzenesulfonato(3-)] [4-[(5-chloro-2-hydroxyphenyl)azo]- 2,4- dihydro-5-methyl-2-phenyl-3H-pyrazol-3-onato(2-)]-, sodium. The study assumed the use of Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 with S9 metabolic activation system. Chromate(2-), [4-[4-[(5-chloro-2- hydroxyphenyl)azo]-4,5-dihydro-3-methyl-5-oxo-1H-pyrazol-1-yl]benzenesulfonato(3-)] [4-[(5-chloro-2-hydroxyphenyl)azo]-2,4-dihydro-5-methyl-2-phenyl-3H- pyrazol-3-onato(2-)]-, sodium was predicted to not induce gene mutation in Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 in the presence of S9 metabolic activation system and hence, according to the prediction made, it is not likely to classify as a gene mutant in vitro.

 

Based on the predicted result it can be concluded that the substance is considered to be not toxic as per the criteria mentioned in CLP regulation.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Genetic toxicity in vivo

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Gene mutation in vitro:

Prediction model based estimation for the target chemical and data from read across chemicals have been reviewed to determine the mutagenic nature of. The studies are as mentioned below:

Based on the prediction done using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the five closest read across substances, gene mutation was predicted for Chromate(2-), [4-[4-[(5-chloro-2-hydroxyphenyl)azo]-4,5-dihydro-3-methyl-5-oxo- 1H-pyrazol-1-yl] benzenesulfonato(3-)] [4-[(5-chloro-2-hydroxyphenyl)azo]- 2,4- dihydro-5-methyl-2-phenyl-3H-pyrazol-3-onato(2-)]-, sodium. The study assumed the use of Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 with and without S9 metabolic activation system. Chromate(2-), [4-[4-[(5-chloro-2- hydroxyphenyl)azo]-4,5-dihydro-3-methyl-5-oxo-1H-pyrazol-1-yl]benzenesulfonato(3-)] [4-[(5-chloro-2- hydroxyphenyl)azo]-2,4-dihydro-5-methyl-2-phenyl-3H- pyrazol-3-onato(2-)]-, sodium was predicted to not induce gene mutation in Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 in the presence and absence of S9 metabolic activation system and hence, according to the prediction made, it is not likely to classify as a gene mutant in vitro.

The above mentioned predicted data iis further supported by the data from read across chemicals as mentioned below:

In a study by Gregory et al (Journal of Applied Toxicology, 1981), Gene mutation toxicity study was performed for 50 -60% structurally similar read across chemical Acid red 97 (RA CAS no 10169 -02 -5) to evaluate its mutagenic nature. The study was performed as per the standard plate incorporation protocol using Salmonella typhimurium strain TA100 and TA98 both in the presence and absence of S9 metabolic activation system. The plates were incubated for 72 hrs before the evaluation of the revertant colonies could be made. Acid red 97 did notinduce gene mutation in the Salmonella typhimurium strain TA100 and TA98 both in the presence and absence of S9 metabolic activation system and hence the chemical is not likely to classify as a gene mutant in vitro.

Bacterial gene mutation test was performed by Venturini and Tamaro (Mutation Research, 1979) to evaluate the mutagenic response for the 82% structurally similar read across chemical Xylene light yellow 2G (RA CAS no 6359 -98 -4; IUPAC name: C.I. acid yellow 17). The test was performed using Salmonella typhimurium strains TA1535, TA100, TA1538, and TA98 in the presence and absence of S9 metabolic activation system using the soft agar overlay method. The test compound was dissolved in DMSO and used at dose levels of 100, 500 or 1000 µg/plate. Concurrent positive control chemicals were also included in the study. Xylene light yellow 2G (C.I. acid yellow 17) did not induce reversion of mutation when applied to Salmonella typhimurium strainsTA1535, TA100, TA1538, and TA98 in the presence and absence of S9 metabolic activation system and hence it is not likely to classify as a gene mutant in vitro.

Based on the data available for the target chemical and its read across, Chromate(2-), [4-[4-[(5-chloro-2-hydroxyphenyl)azo]-4,5-dihydro-3-methyl-5-oxo- 1H-pyrazol-1-yl] benzenesulfonato(3-)] [4-[(5-chloro-2-hydroxyphenyl)azo]- 2,4- dihydro-5-methyl-2-phenyl-3H-pyrazol-3-onato(2-)]-, sodium does not exhibit gene mutation in vitro. Hence the test chemical is not likely to classify as a gene mutant as per the criteria mentioned in CLP regulation.

Justification for classification or non-classification

Based on the data available for the target chemical and its read across, Chromate(2-), [4-[4-[(5-chloro-2-hydroxyphenyl)azo]-4,5-dihydro-3-methyl-5-oxo- 1H-pyrazol-1-yl] benzenesulfonato(3-)] [4-[(5-chloro-2-hydroxyphenyl)azo]- 2,4- dihydro-5-methyl-2-phenyl-3H-pyrazol-3-onato(2-)]-, sodium (CAS 90294 -36 -3) does not exhibit gene mutation in vitro. Hence the test chemical is not likely to classify as a gene mutant as per the criteria mentioned in CLP regulation.